From the Guidelines
Taking a 30 mg zinc picolinate supplement daily can potentially cause copper deficiency over time, as high zinc intake can interfere with copper absorption, and the recommended daily intake of zinc should not exceed 40 mg from all sources 1. This typically occurs after several months of continuous high-dose zinc supplementation, though the exact timeframe varies based on individual factors like diet and initial copper status.
Key Considerations
- Zinc and copper compete for absorption in the intestines, and high zinc intake can reduce copper absorption.
- For most adults, zinc intake should not exceed 40 mg daily from all sources.
- To prevent copper deficiency while taking zinc supplements, consider:
- Limiting supplementation to 15-30 mg daily
- Taking zinc separate from copper-containing foods or supplements
- Monitoring for symptoms like fatigue and anemia
- Possibly adding a copper supplement (1-2 mg daily) if long-term zinc supplementation is necessary
- Maintaining a balanced diet containing copper-rich foods like shellfish, nuts, seeds, and dark chocolate
Recent Guidelines
The British Obesity and Metabolic Surgery Society guidelines recommend a multivitamin and mineral supplement containing at least the government-recommended daily allowance for zinc, and suggest starting with 15 mg daily zinc supplementation after certain bariatric surgeries, while also recommending 2 mg daily copper supplementation 1.
Monitoring and Prevention
Regular monitoring of zinc and copper levels is essential, especially when taking high-dose zinc supplements, to prevent zinc-induced copper deficiency and ensure a balanced ratio of 8-15 mg of zinc for each 1-mg copper 1.
From the FDA Drug Label
Administration of zinc in the absence of copper may cause a decrease in serum copper levels. Periodic determinations of serum copper as well as zinc are suggested as a guideline for subsequent zinc administration
Daily supplementation with 30 milligrams of zinc picolinate (Zn) may lead to copper (Cu) deficiency, specifically hypocupremia, if copper intake is not adequate.
- The exact amount of zinc that can cause copper deficiency is not specified in the label.
- It is recommended to monitor serum copper levels during zinc supplementation. 2
From the Research
Zinc Supplementation and Copper Deficiency
- Daily supplementation with 30 milligrams of zinc picolinate (Zn) can lead to copper (Cu) deficiency, specifically hypocupremia, as high intakes of zinc relative to copper can cause copper deficiency 3, 4, 5.
- The European Food Safety Authority (EFSA) defines the tolerable upper intake level (UL) as 25 mg per day, whereas the Food and Drug Administration (FDA) allows 40 mg per day, and exceeding these limits may result in symptoms such as anemia, neutropenia, and zinc-induced copper deficiency 4.
- Evidence suggests that even lower levels of zinc supplementation, closer in amount to the Recommended Dietary Allowance (RDA), have been suggested to interfere with the utilization of copper and iron and to adversely affect HDL cholesterol concentrations 5.
- Case reports have shown that zinc supplementation can induce copper deficiency, leading to severe leukocytopenia, anemia, and other symptoms, particularly in patients with certain medical conditions or dietary habits 6, 7.
Mechanisms and Risks
- The mechanism of zinc-induced copper deficiency is thought to be related to the inhibition of copper absorption in the intestine, which can lead to a decrease in serum copper and ceruloplasmin levels 7.
- The risk of copper deficiency is higher in individuals who take high doses of zinc supplements, have a poor diet, or have certain medical conditions, such as peritoneal dialysis 6.
- Monitoring of copper levels and careful assessment of dietary history are essential to avoid copper deficiency in patients taking zinc supplements 6.